package string;

public class StringBuilderDemo {
    public static void main(String[] args) {
//        StringBuilder builder1 = new StringBuilder();
//        StringBuilder builder2 = new StringBuilder("abc");
//
//        String str = "abc";
//        StringBuilder builder3 = new StringBuilder(str);
//        String str2 = builder3.toString();

        String str = "好好学习java";
        StringBuilder builder = new StringBuilder(str);

        builder.append(",为了找个好工作");
        System.out.println(builder);

        builder.replace(9,16,"就是为了改变世界");
        System.out.println(builder);

        builder.delete(0,8);
        System.out.println(builder);

        builder.insert(0,"活着");
        System.out.println(builder);






    }

}
